Problem with CQL filter

[bvst]

Hi!
After adding a collection of jsonArray data to my mongodb database I wanted to filter it with CQL, but it doesn't seem to work.
My query goes like this : user.name like '%username%'
When I apply this filter all my points disappair...
The only CQL filter that seems to work is when I try an int value on a root property:
id_str = 123

Versions I am using:
mongodb: 3.0.2
geoserver: 2.7.0
geoserver-exts: 2.7-SNAPSHOT

Are there any known issues around this? Any help will be much appreciated.